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<strong>Electrosurgery</strong><br />

<strong>Self</strong>-<strong>Study</strong> <strong>Guide</strong>


Brenda Cole Ulmer, RN, MN, CNOR<br />

Brenda C. Ulmer is a Senior Clinical Educator for Valleylab. In this capacity<br />

she creates and presents programs of importance to perioperative nurses<br />

and surgeons on topics focusing on patient safety in the operating room.<br />

Prior to this position, Ms. Ulmer was Director of Surgical Services at<br />

Northlake Regional Medical Center in Atlanta, Georgia. Previous work<br />

experience includes staff charge positions at Emory University Hospital in<br />

Atlanta.<br />

Ulmer received an associate degree in nursing in 1974 from DeKalb<br />

College, a bachelors in 1983 from Georgia State University, and a<br />

masters in nursing education from the University of Phoenix in 1996.<br />

She has been a certified nurse of the operating room (CNOR) since<br />

1980. Ulmer is also a member of Sigma Theta Tau’s nursing honor<br />

society.<br />

Ulmer has served on local and national committees for the<br />

Association<br />

of periOperative Registered Nurses (AORN) since 1977. She served<br />

three terms as member of the national AORN Board of Directors, and<br />

was elected President-Elect for AORN on April 1, 1999 in San<br />

Francisco. Since 1995, Ulmer has been working with the AORN,<br />

OSHA, NIOSH, ANA, physicians and nurses to facilitate the publication<br />

of workplace safety guidelines<br />

from OSHA on smoke evacuation. OSHA signed off the draft<br />

guidelines internally in the spring of 1998. They are currently under<br />

final review for publication in the Federal Register in 1999.<br />

From 1989 to 1994, Ulmer was a member of the CBPN Board of<br />

Directors (CBPN Formerly NCB: PNI). She served as President 1990-<br />

91 and 1993-94. During her tenure the Board published its first<br />

CNOR <strong>Study</strong> <strong>Guide</strong>, and started a Registered Nurses First Assistant<br />

Certification exam (CRNFA).<br />

Ms. Ulmer has presented numerous programs on nursing issues<br />

throughout the world. In 1983 she published the first nursing text on<br />

ambulatory surgery: Ambulatory Surgery: A <strong>Guide</strong> to Perioperative<br />

Nursing Care. She is widely published in nursing journals and textbooks.


ELECTROSURGERY<br />

SELF-STUDY GUIDE<br />

September, 1999<br />

A self-study guide intended to assist<br />

surgeons, perioperative nurses and<br />

other healthcare team members to<br />

provide safe and effective patient care<br />

during electrosurgery procedures.<br />

by<br />

Brenda C. Ulmer, RN, MN, CNOR<br />

<strong>Electrosurgery</strong> <strong>Self</strong>-<strong>Study</strong> <strong>Guide</strong><br />

3


<strong>Electrosurgery</strong> <strong>Self</strong>-<strong>Study</strong> <strong>Guide</strong><br />

Objectives<br />

Upon completion of this activity the participant will be able to:<br />

4<br />

1.) Relate the properties of electricity to the clinical<br />

applications of electrosurgery.<br />

2.) Review four of the variables the surgeon controls<br />

that impact surgical effect.<br />

3.) Discuss the relationship between current<br />

concentration and tissue effect.<br />

4.) Identify potential patient injuries related to electro<br />

surgery and technological advances designed to<br />

eliminate these problems.<br />

Accreditation<br />

Statements<br />

This activity has been planned and implemented in<br />

accordance with the Essentials and Standard of the<br />

Accreditation Council for Continuing Medical Education by<br />

Valleylab. Valleylab is accredited by the ACCME to provide<br />

continuing medical education for physicians<br />

Valleylab designates this educational activity for a<br />

maximum of 2 hours in Category 1 credit toward the AMA<br />

Physician’s Recognition Award. Each physician should<br />

claim only those hours of credit that he/she actually spent<br />

in the educational activity.<br />

This offering for two (2) contact hours was designed by the<br />

Clinical Education Department of Valleylab, which is an<br />

approved provider of nursing continuing education (CE) in:<br />

Colorado: Valleylab is approved as a provider of<br />

continuing education in nursing by the<br />

Colorado Nurses’ Association, which is<br />

accredited as an approver of continuing<br />

education in nursing by the American<br />

Nurses Credentialing Center’s<br />

Commission on Accreditation.<br />

Additional Valleylab provider numbers:<br />

California: #CEP 12764<br />

Iowa: #289<br />

Florida: #27I1796<br />

Kansas: #LT0134-0327<br />

Disclaimer Statement<br />

CNA “approved” refers to recognition of educational<br />

offerings only and does not imply approval or<br />

endorsement of any product of Valleylab.<br />

A certificate of completion pertains only to the participant’s<br />

completion of the self-study guide and does not, in any way,<br />

attest to the clinical competence of any participant.<br />

Verification of<br />

Completion<br />

A certificate will be provided to each person who<br />

completes the offering. The certificate pertains only to<br />

completion of the offering and is intended for recordkeeping<br />

purposes.<br />

Instructions<br />

1. Complete the test questions and check the correct<br />

responses with the key. A score of 70% or better is<br />

recommended. Please review the self-study guide<br />

portions related to missed questions, if necessary.<br />

2. Complete the registration form.<br />

3. Complete the evaluation form.<br />

4. Send the completed registration/evaluation form<br />

with the test question responses and $15.00 fee to:<br />

Clinical Education Department A50<br />

Valleylab<br />

5920 Longbow Drive<br />

Boulder, CO 80301-3299<br />

For information call: 800-255-8522 EXT. 6240<br />

5. Upon receipt of the required documents a certificate<br />

of completion for two (2) credit/contact hours will be<br />

sent. Please allow 3–4 weeks for the certificate to be<br />

mailed after submission of required paperwork.<br />

Valleylab will maintain a record of your continuing<br />

education credit and provide verification if necessary<br />

for five (5) years.<br />

Expiration Date<br />

This offering was originally produced for distribution in<br />

September 1997. It was revised in September 1999 and<br />

cannot be used after September 2002 without being<br />

updated. Therefore, credit will not be issued after<br />

September 30, 2002.<br />

Note: The terms listed in the glossary are printed in bold in<br />

the body of the text of the self-study guide.<br />

Key Concepts<br />

Electricity can be hazardous. Understanding how<br />

electricity behaves and relates to electrosurgical function<br />

and applications can contribute to its safe use. Many<br />

different types of electrosurgical technologies are in use in<br />

the surgical setting. The surgeon, perioperative nurse and<br />

other healthcare team members must be aware of the<br />

implications for use for each technology in order to ensure<br />

safe patient care.


Knowledge of the preoperative, intraoperative and<br />

postoperative medical and nursing considerations and<br />

interventions can impact positive patient outcomes.<br />

Overview<br />

<strong>Electrosurgery</strong> came into wide use because of the urgent<br />

need to control bleeding in operative procedures. There have<br />

always been safety concerns when electricity is used in a<br />

therapeutic manner. This module will cover the fundamentals<br />

of electricity, principles of electrosurgery, clinical applications,<br />

technologies, recommended practices and nursing care<br />

during electrosurgery.<br />

Introduction<br />

The use of heat to stop bleeding goes back hundreds of years.<br />

Over the years researchers constructed a variety of devices<br />

which used electricity as a means to heat tissue and control<br />

bleeding. <strong>Electrosurgery</strong> did not come into general use until<br />

the late 1920’s. A neurosurgeon, Harvey Cushing, worked<br />

with a physicist, William T. Bovie, in efforts to develop a<br />

means to stop hemorrhage with electricity. Cushing had tried<br />

implanting muscle tissue, using bone wax, fibrin clots, and<br />

silver clips, but still had patients who could not be operated<br />

on safely because of the threat of uncontrolled bleeding. In<br />

1926, using Bovie’s device, Cushing applied high frequency<br />

current during a neurosurgical procedure. The results were<br />

excellent. Cushing then started bringing back his previously<br />

inoperable patients because he at last had a means to prevent<br />

death from hemorrhage in the operating room (Pearce,<br />

1986). Cushing and Bovie widely published their work. As a<br />

result electrosurgical units came into general use in operating<br />

rooms around the world. The early units were big, ground<br />

referenced units called Bovie’s. The technology remained<br />

virtually unchanged until 1968 when a small, solid state unit<br />

was developed by Valleylab. The solid state units heralded<br />

the modern era of isolated outputs, complex waveforms, and<br />

hand-activated controls (Pearce).<br />

Fundamentals<br />

of Electricity<br />

Electricity is a phenomenon arising from the existence of<br />

positively and negatively charged particles, which make<br />

up all matter. All matter is made up of atoms. Atoms<br />

consist of electrons (negatively charged), protons<br />

(positively charged), and neutrons (neutral) particles.<br />

Atoms that contain equal numbers of electrons and<br />

protons are charge neutral. When forces are introduced<br />

that cause electrons to leave their base atoms and move<br />

to other atoms, the charges of the atom are changed:<br />

those with fewer electrons than protons become<br />

<strong>Electrosurgery</strong> <strong>Self</strong>-<strong>Study</strong> <strong>Guide</strong><br />

positively charged, and atoms with more electrons than<br />

protons become negatively charged. During movement,<br />

like charges repel each other and unlike charges attract.<br />

This electron movement is termed electricity. There are<br />

two natural properties of electricity that can impact<br />

patient care in the operating room. Electricity, which<br />

moves at nearly the speed of light, will, (1) always follow<br />

the path of least resistance; and, (2) always seek to return<br />

to an electron reservoir like the ground (Chernow, 1993).<br />

Electrical current is produced as electrons flow through a<br />

conductor. Electron flow is measured in amperes, or<br />

amps. The path electricity follows as it makes its way<br />

through a conductor and back to ground is the electrical<br />

circuit.<br />

Electricity Variables<br />

There are variables associated with electricity that must<br />

be considered when using it in a therapeutic manner.<br />

Current<br />

The two types of current that are used in the operating<br />

room are direct current (DC), and alternating current (AC).<br />

Direct current uses a simple circuit and electron flow is<br />

only in one direction. Batteries employ this simple circuit.<br />

Energy flows from one terminal on the battery and must<br />

return to the other terminal to complete the circuit.<br />

Alternating currents (AC) switch, or alternate, direction of<br />

electron flow. The frequency of these alterations is<br />

measured in cycles per second or Hertz (Hz), with one<br />

Hertz being equal to one cycle per second. Household<br />

current, in the United States, alternates at 60 cycles per<br />

second, as does much of the electrical equipment used in<br />

operating rooms. Alternating current at 60 Hertz causes<br />

tissue reaction and damage. Neuromuscular stimulation<br />

ceases at about 100,000 Hertz, as the alternating currents<br />

move into the radio frequency (RF)range (Grundemann,<br />

1995).<br />

Resistance<br />

Resistance is the opposition to the flow of current.<br />

Resistance or impedance is measured in ohms. During<br />

the use of electrosurgery one source of resistance or<br />

impedance is the patient.<br />

5


<strong>Electrosurgery</strong> <strong>Self</strong>-<strong>Study</strong> <strong>Guide</strong><br />

Voltage<br />

Voltage is the force that will cause one amp to flow<br />

through one ohm of resistance. It is measured in volts.<br />

The voltage in an electrosurgical generator provides the<br />

electromotive force that pushes electrons through the<br />

circuit.<br />

Power<br />

Power is the energy produced. The energy is measured in<br />

watts. In electrosurgical generators the power setting<br />

used by the surgeon is either displayed on an LED screen<br />

in watts; or, a percentage of the total wattage as indicated<br />

on a numerical dial setting (Lister, 1984).<br />

Principles of<br />

<strong>Electrosurgery</strong><br />

Electrocautery<br />

The electrocautery device is the simplest electrical<br />

system used in the operating room today. It uses battery<br />

power to generate a simple direct current (DC). The<br />

current never leaves the instrument to travel through the<br />

patient’s tissue. An example is the small hand-held eye<br />

cautery (Figure 1). The battery heats up a wire loop at the<br />

end of the device. The cautery is useful in ophthalmic<br />

surgery and other very minor procedures in which very<br />

little bleeding is encountered. Its use is limited because it<br />

cannot cut tissue or coagulate large bleeders. It is further<br />

limited because the target tissue tends to stick to the<br />

electrode.<br />

The term “electrocautery,” or “cautery,” is often, and<br />

incorrectly, used to describe all types of electrosurgical<br />

devices. Its use is only appropriate to describe the simple<br />

direct current cautery device.<br />

Figure 1 – Electrocautery<br />

6<br />

<strong>Electrosurgery</strong> and Radio Frequency<br />

Current<br />

A frequently asked question is why electrosurgery<br />

generators do not shock patients. The answer is because<br />

of the higher frequencies at which generators operate.<br />

Radio frequency current alternates so rapidly that cells do<br />

not react to this current. AM radio stations operate in the<br />

550 to 1500 KiloHertz (kHz) range. <strong>Electrosurgery</strong><br />

generators operate in the 200 kHz to 3.3 megahertz<br />

(MHz) range (Figure 2). Both of these are well above the<br />

range where neuromuscular stimulation or electrocution<br />

could occur (Harris, 1978).<br />

60 Hz 100 kHz 550 - 1550 kHz 54 - 880 M<br />

Household<br />

Appliances<br />

Muscle and Nerve<br />

Stimulation Ceases<br />

<strong>Electrosurgery</strong><br />

Figure 2 – Frequency Spectrum<br />

200 kHz - 3.3 MHz<br />

AM Radio TV


Bipolar <strong>Electrosurgery</strong><br />

Bipolar electrosurgery is the use of electrical current<br />

where the circuit is completed by using two parallel poles<br />

located close together. One pole is positive and the other<br />

is negative. The flow of current is restricted between<br />

these two poles. These are frequently tines of forceps, but<br />

may also be scissors or graspers. Because the poles are in<br />

such close proximity to each other, low voltages are used<br />

to achieve tissue effect. Most bipolar units employ the cut<br />

waveform because it is a lower voltage waveform, and<br />

achieves hemostasis without unnecessary charring.<br />

Because the current is confined to the tissue between the<br />

poles of the instrument and does not flow through the<br />

patient, a patient return electrode is not needed (Figure<br />

3).<br />

Figure 3 – Bipolar Circuit<br />

Bipolar is a very safe type of electrosurgery. There are<br />

some disadvantages to the use of bipolar, especially in the<br />

microbipolar mode. Bipolar cannot spark to tissue, and<br />

the low voltage makes it less effective on large bleeders<br />

(Mitchell, 1978). However, there are newer bipolar<br />

systems that incorporate a “macro” or bipolar “cut” mode<br />

that has higher voltage and is designed for use with the<br />

new generation of bipolar cutting instruments.<br />

Bipolar, especially microbipolar, has been widely used in<br />

neurosurgery and gynecologic surgery. It may be safer to<br />

use when there is a question about the efficacy of using<br />

more powerful monopolar electrosurgical units (e.g., with<br />

pacemakers, implanted automatic cardiac defibrillators).<br />

Monopolar <strong>Electrosurgery</strong><br />

The most frequently used method of delivering<br />

electrosurgery is monopolar, because it delivers a greater<br />

range of tissue effects. In monopolar electrosurgery, the<br />

generator produces the current, which travels through an<br />

active electrode and into target tissue. The current then<br />

passes through the patient’s body to a patient return<br />

electrode where it is collected and carried safely back to<br />

<strong>Electrosurgery</strong> <strong>Self</strong>-<strong>Study</strong> <strong>Guide</strong><br />

the generator (Figure 4). This is the intended pathway for<br />

the electrical current. The type of monopolar generator<br />

used, along with appropriate surgeon and nursing<br />

interventions can help to ensure that this is the path the<br />

current takes through the patient.<br />

Figure 4 – Monopolar Circuit<br />

Current Concentration/Density<br />

The purpose of both methods of delivery is to produce<br />

heat for a desired surgical effect. When current is<br />

concentrated, heat is produced. The amount of heat<br />

produced determines the extent of the tissue effect.<br />

Current concentration or density depends on the size of<br />

the area through which the current flows. A small area<br />

that concentrates the current offers more resistance,<br />

which necessitates more force to push the current<br />

through the limited space and therefore generates more<br />

heat. A large area offers less resistance to the flow of<br />

current reducing the amount of heat produced (Figure 5).<br />

Low Current<br />

Concentration<br />

Figure 5 – Current Concentration/Density<br />

High Current<br />

Concentration<br />

7


<strong>Electrosurgery</strong> <strong>Self</strong>-<strong>Study</strong> <strong>Guide</strong><br />

Electrosurgical Mode<br />

Differentiation<br />

Electrosurgical generators can produce current in three<br />

different modes, each with distinct tissue effects. The<br />

modes are cut, fulguration and desiccation.<br />

Electrosurgical Cut<br />

The cutting current is a continuous waveform (Figure 6).<br />

Figure 6 – Cut Waveform<br />

Since the delivery of current is continuous, much lower<br />

voltages are required to achieve the desired effect of<br />

tissue vaporization. To achieve a cutting effect, the tip of<br />

the active electrode should be held just over the target<br />

tissue. The current vaporizes cells in such a way that a<br />

clean tissue cut is achieved (Figure 7). The cut mode of<br />

the generator is also a good choice for achieving<br />

coagulation of tissue through desiccation.<br />

Figure 7 – Vaporization or Cutting<br />

Blended Mode<br />

The blended mode on a generator is a function of the cut<br />

waveform. Blended currents produce voltages higher<br />

than that of the pure cut mode. The generator output is<br />

modified to a dampened waveform that produces some<br />

hemostasis during cutting (Tucker, 1998). There are<br />

several blended waveforms that provide different ratios of<br />

coagulation with the cutting current by modifying the<br />

8<br />

PURE CUT<br />

100% on<br />

duty (on/off) cycle (Figure 8). Examples of blend<br />

waveforms from different generators are:<br />

Blend 1 = 50% on/50% off<br />

Blend 2 = 40% on/60% off<br />

Blend 3 = 25% on/75% off<br />

Variations of cut to coagulation blends may occur among<br />

manufacturers. Generally, however, a higher blend<br />

number means more coagulation.<br />

Figure 8 – Blended Waveforms<br />

Fulguration<br />

BLEND 1 BLEND 2 BLEND 3<br />

50% on<br />

50% off<br />

40% on<br />

60% off<br />

Tissue fulguration is achieved with the coagulation mode<br />

on the generator. The coagulation mode produces an<br />

interrupted or dampened waveform with a duty cycle that<br />

is on about 6% of the time (Figure 9).<br />

COAG<br />

6% on<br />

94% off<br />

Figure 9 – Coagulation Waveform<br />

25% on<br />

75% off<br />

The coagulation current produces spikes of voltage as<br />

high as 5000 volts at 50 watts. The tissue is heated when<br />

the waveform spikes, and cools down in between spikes,<br />

thus producing coagulation of the cell during the 94% off<br />

cycle of he waveform.


The correct method for achieving fulguration when using<br />

coagulation is to hold the tip of the active electrode<br />

slightly above the target tissue (Figure 10).<br />

Figure 10 – Fulguration<br />

Desiccation<br />

Electrosurgical desiccation can be produced using either<br />

the cut or coagulation mode on the generator. The<br />

difference between fulguration and desiccation is that<br />

the tip of the active electrode must contact the target<br />

tissue in order to achieve desiccation (Figure 11). The<br />

desired mode to achieve tissue desiccation through direct<br />

contact is the cut waveform.<br />

CUT<br />

Low voltage<br />

waveform<br />

100% duty<br />

cycle<br />

Figure 11 – Desiccation<br />

COAG<br />

High voltage<br />

waveform<br />

6% duty cycle<br />

Other Variables That Impact Tissue Effect<br />

The electrosurgical mode that the surgeon uses has a<br />

definite impact on patient tissue. There are other variables<br />

that can also alter the outcome of the electrosurgical<br />

tissue effect:<br />

TIME – The length of time that the surgeon uses the active<br />

electrode determines the amount of tissue effect. Too long<br />

an activation time will produce wider and deeper tissue<br />

damage. Too short an activation time will not produce the<br />

desired tissue effect.<br />

<strong>Electrosurgery</strong> <strong>Self</strong>-<strong>Study</strong> <strong>Guide</strong><br />

POWER – The power setting the surgeon uses will alter<br />

tissue effect. The surgeon should always use the lowest<br />

setting to achieve the desired tissue effect. The setting will<br />

differ from patient to patient. Muscular patients of weight<br />

and height in proper portions will require lower power<br />

settings than obese or emaciated patients. The location of<br />

the return electrode in relation to the surgical site will<br />

impact the power required to overcome the amount of<br />

tissue mass (resistance) between the two (2) sites.<br />

ELECTRODE – The size of the active electrode influences<br />

the tissue effect of the generator. A large electrode needs<br />

a higher power setting than a smaller one because the<br />

current is dispersed over a wider surface area (Figure 12).<br />

A clean electrode will need less power to do the same<br />

work as a dirty one because eschar buildup has higher<br />

resistance and will hamper the passage of the current.<br />

Electrodes can be coated with Teflon (PTFE) or an<br />

elastomeric silicone coating to reduce eschar buildup.<br />

These coated blades wipe clean with a sponge and<br />

eliminate that need for a “scratch pad” which causes<br />

grooves on stainless steel electrodes that may contribute<br />

to eschar build-up. These different types of blades should<br />

be evaluated because some will enable the surgeon to use<br />

lower power settings, reducing the potential for thermal<br />

spread. In addition, some coated electrodes are bendable,<br />

have a non-flake coating and retain their cleaning<br />

properties longer than other coated electrodes.<br />

Low current<br />

concentration<br />

(density)<br />

increases<br />

Current Concentration & Heat<br />

decreases increases<br />

Electrode size<br />

Power Setting Requirement<br />

decreases<br />

High current<br />

concentration<br />

(density)<br />

Figure 12 – Current Concentration Effect on Power Settings<br />

TISSUE – Patient tissue can determine the effectiveness<br />

of the generator. The physical characteristics of the<br />

patient’s body will determine the amount of impedance<br />

encountered by the electrosurgical current as it attempts<br />

to complete the circuit through the return electrode to the<br />

generator. A lean muscular patient will conduct the<br />

electrosurgical current much better than an obese or an<br />

emaciated patient.<br />

9


<strong>Electrosurgery</strong> <strong>Self</strong>-<strong>Study</strong> <strong>Guide</strong><br />

Electrosurgical<br />

Technologies<br />

As the sophistication of surgical procedures has evolved<br />

over time, so too have electrosurgical technologies.<br />

Meeting the challenge of improved patient care is but one<br />

of the goals of the medical manufacturing partner within<br />

the health care arena. The surgeon and perioperative<br />

nurse must be familiar with both long-standing<br />

technologies and with emerging ones so that the safest<br />

and most effective care is available to patients.<br />

Ground-Referenced Generators<br />

The first generation of electrosurgery units that were<br />

developed in the early 1900’s were ground-referenced.<br />

When using these units, it is earth ground that completes<br />

the electrosurgical circuit. These units were spark-gap<br />

systems with high output and high performance<br />

(Hutchisson, 1998), making them popular with surgeons.<br />

The major hazard when using a grounded system is that<br />

current division can occur. If the electrical current finds<br />

an easier (lower resistance) and quicker way to return to<br />

ground, and if the current were sufficiently concentrated,<br />

the patient could be burned at any point where the current<br />

exits the patient’s body (Figure 13).<br />

Figure 13 – Current Division<br />

This could be where the patient’s hand touches the side of<br />

the OR bed, a knee touches a stirrup, or any number of<br />

alternate exit sites (Figure 14).<br />

10<br />

Figure 14 – Alternate Site Burn<br />

In early models of ground-referenced generators, the<br />

surgeon could use electrosurgery regardless of whether a<br />

patient return electrode was attached to the patient. This<br />

resulted in patient burns. Later models offered a cord fault<br />

alarm, which alerted the staff if the patient return<br />

electrode was not plugged into the generator. The<br />

disadvantage was that electrosurgery could still be used<br />

even if the patient return electrode was not on the<br />

patient. Burns could also occur at the return electrode site.<br />

In 1995 the Emergency Care Research Institute (ECRI)<br />

stated that “spark-gap units are outdated and have been<br />

largely superseded by modern technology”. The Institute<br />

recommended that hospitals with surgeons who still insist<br />

on using ground-referenced units should obtain signed<br />

statements from these surgeons acknowledging the risk<br />

of using spark-gap electrosurgical units (Kirshenbaum,<br />

1996).<br />

Solid-State Generators<br />

Solid-state generators were introduced in 1968. These<br />

units were much smaller and used “isolated” circuitry. In<br />

isolated units, the electrical current produced by the<br />

generator is referenced to the generator and will ignore all<br />

grounded objects that may touch the patient except the<br />

return electrode. With isolated generators current<br />

division cannot occur and there is no possibility of<br />

alternate site burns (Figure 15).


Figure 15 – Isolated Circuit<br />

An isolated generator will not work unless the patient<br />

return electrode is attached to the patient. However,<br />

without additional safety features, the generator cannot<br />

determine the status of the contact at the pad/patient<br />

interface. Should the patient return electrode be<br />

compromised in the quantity or quality of the pad/patient<br />

interface in some way during surgery, a return electrode<br />

burn could occur (Figure 16). The perioperative nurse<br />

must be certain that the patient return electrode is in<br />

good contact with the patient throughout the surgical<br />

procedure.<br />

Figure 16 – Pad Site Burn<br />

Contact Quality Monitoring<br />

Patient return electrodes employing a contact quality<br />

monitoring system were introduced in 1981. Contact<br />

quality monitoring uses a split pad system whereby an<br />

interrogation current constantly monitors the quality of the<br />

contact between the patient and the patient return<br />

electrode (Figure 17).<br />

<strong>Electrosurgery</strong> <strong>Self</strong>-<strong>Study</strong> <strong>Guide</strong><br />

Figure 17 – Return Electrode Monitoring System<br />

If a condition develops at the patient return electrode<br />

site that could result in a patient burn, the system<br />

inactivates the generator while giving audible and visual<br />

alarm signals. This represents a major safety device for<br />

patients and perioperative personnel since return<br />

electrode burns account for a majority of patient burns<br />

during electrosurgery. According to ECRI many<br />

electrosurgery burns could be eliminated by a patient<br />

return electrode quality contact monitoring system (ECRI,<br />

1999).<br />

Monopolar Electrosurgical Hazards<br />

During Minimally Invasive Surgery<br />

In the past few years the number of laparoscopic<br />

procedures has risen dramatically and is expected to<br />

continue (Figure 18) (MDI, 1996).<br />

1800<br />

1400<br />

1200<br />

1000<br />

800<br />

600<br />

Procedure Volume in 000’s 1600<br />

400<br />

200<br />

0<br />

Estimated Increase in Laparoscopy for the Six Leading<br />

General Surgical Procedures by Volume<br />

1994 2000<br />

Open<br />

Laparoscopic<br />

Figure 18 – Estimated Increase in Laparoscopy for the Six<br />

Leading General Surgical Procedures by Volume<br />

11


<strong>Electrosurgery</strong> <strong>Self</strong>-<strong>Study</strong> <strong>Guide</strong><br />

This increase has brought concerns about monopolar<br />

electrosurgery when used during minimally invasive<br />

procedures. There have been reports of severe illness and<br />

death following laparoscopy where use of electrosurgery<br />

has been implicated as a cause (ECRI, 1995). The hazards<br />

associated with endoscopic electrosurgery use are:<br />

12<br />

• direct coupling<br />

• insulation failure<br />

• capacitive coupling<br />

Each of these can cause severe patient injury if the current<br />

is highly concentrated at the point of contact.<br />

In determining when and how these hazards occur, it is<br />

useful to divide the active electrode and cannula system<br />

into four zones (Figure 19).<br />

One intended<br />

Three unintended<br />

Zone 1 Zone 2 Zone 3 Zone 4<br />

Figure 19 – Four Zones of Injury<br />

Zone 1 is the area at the tip of the active electrode in<br />

view of the surgeon. Zone 2 encompasses the area just<br />

outside the view of the surgeon to the end of the cannula.<br />

Zone 3 is the area of the active electrode covered by the<br />

cannula system. This is also outside the view of the<br />

surgeon. Zone 4 is the portion of the electrode and<br />

cannula that is outside the patient’s body. The greatest<br />

concern is the unseen incidence of stray electrosurgery<br />

current in Zones 2 and 3 (Harrell, 1998).<br />

Direct coupling occurs when the active electrode is<br />

activated in close proximity or direct contact with other<br />

conductive instruments within the body. This can occur<br />

within Zones 1, 2, or 3. If it occurs outside the field of<br />

vision and the current is sufficiently concentrated a patient<br />

injury can occur.<br />

Insulation failure occurs when the coating that is applied<br />

to insulate the active electrode is compromised. This can<br />

happen in multiple ways that range from repeated uses to<br />

rough handling to using very high voltage current. There is<br />

also concern that some active electrodes may not meet<br />

the standards for electrosurgical devices set by the<br />

Association for the Advancement of Medical<br />

Instrumentation (AAMI), and the American National<br />

Standards Institute (ANSI). Insulation failure that occurs<br />

in Zones 2 or 3 could escape detection by the surgeon<br />

and cause injury to adjacent body structures if the current<br />

is concentrated (Figure 20).<br />

Figure 20 – Insulation Failure<br />

Capacitive coupling is the least understood of the<br />

endoscopic electrosurgical hazards. Anytime two<br />

conductors are separated by an insulator a capacitor is<br />

created. For example, a capacitor is created by inserting<br />

an active electrode, surrounded by its insulation, down a<br />

metal cannula (Figure 21).<br />

Abdominal Wall<br />

Laparoscopic View<br />

Conductor<br />

(Electrode Tip)<br />

Insulator<br />

(Electrode Insulation)<br />

Conductor<br />

(Metal Cannula)<br />

Figure 21 – Instrument/Metal Cannula Configuration<br />

Capacitively coupled electrical current can be transferred<br />

from the active electrode, through intact insulation and<br />

into the conductive metal cannula. Should the cannula<br />

then come in contact with body structures, that energy<br />

can be discharged into these structures and damage them<br />

(Harrell). With an all-metal cannula, electrical energy<br />

stored in the cannula will tend to disperse into the patient<br />

through the relatively large contact area between the<br />

cannula and the body wall. Because the contact area is<br />

relatively large, the electrical energy is less concentrated<br />

and less dangerous. For this reason it is unwise to use


plastic anchors to secure the cannula because it isolates<br />

the current from the body wall. Some institutions use<br />

plastic trocar cannula systems because they wrongly<br />

believe them to be safer. The plastic systems can also be<br />

dangerous because the patient’s own conductive tissue<br />

within the body can form the second conductor, creating a<br />

capacitor. The patient’s omentum or bowel draped over<br />

the plastic cannula could discharge stored energy to<br />

adjacent body structures.<br />

Recommendations to avoid electrosugical complications<br />

during minimally invasive surgery are:<br />

• Inspect insulation carefully<br />

• Use lowest possible power setting<br />

• Use low voltage (cut) waveform<br />

• Use brief intermittent activation vs. prolonged<br />

activation<br />

• Do not activate in open circuit<br />

• Do not activate electrode in close proximity or direct<br />

contact with metal/conductive object<br />

• Use bipolar electrosurgery when appropriate<br />

• In the operative channel for activated electrodes<br />

- Select an all metal cannula system as the safest<br />

choice<br />

- Do not use a hybrid system (metal and plastic<br />

components)<br />

• Utilize available technology<br />

- Tissue response generator to reduce capacitive<br />

coupling in the low voltage waveform<br />

- Active electrode monitoring system to eliminate<br />

concerns with insulation failure and capacitive<br />

coupling<br />

Active Electrode Monitoring<br />

The risks posed to the patient by insulation failure and<br />

capacitive coupling can be alleviated with active<br />

electrode monitoring. The active electrode monitoring<br />

system is used together with the electrosurgical unit<br />

(Figure 22). When in place, this system continuously<br />

monitors and actively shields against stray electrosurgical<br />

current. According to ECRI, active electrode monitoring is<br />

the most effective means to minimize the potential for<br />

patient injuries due to insulation failure or capacitive<br />

coupling (Kirshenbaum, 1996).<br />

Exposed Active<br />

Electrode<br />

Integrated Electrode<br />

Conductive Shield<br />

Outer Insulator<br />

Internal Active Insulator<br />

Trocar Cannula<br />

Figure 22 – Active Electrode Monitoring<br />

<strong>Electrosurgery</strong> <strong>Self</strong>-<strong>Study</strong> <strong>Guide</strong><br />

Argon Enhanced <strong>Electrosurgery</strong><br />

In the late 1980’s an argon delivery system was combined<br />

with electrosurgery to create argon enhanced<br />

electrosurgery. This modality of electrosurgery should not<br />

be confused with a laser. The argon gas shrouds the<br />

electrosurgery current in a stream of ionized gas that<br />

delivers the spark to tissue in a beam-like fashion (Figure<br />

23). Argon is an inert, nonreactive gas. It is heavier than<br />

air, and easily ionizes. Because the beam concentrates the<br />

electrosurgical current a smoother, more pliable eschar is<br />

produced. In addition, the argon disperses blood,<br />

improving visualization. Because the heavier argon<br />

displaces some of the oxygen at the surgical site, less<br />

smoke is produced. When used during surgery, argonenhanced<br />

electrosurgery can reduce blood loss and<br />

surgical time (Rothrock, 1999).<br />

Figure 23 – Argon Enhanced <strong>Electrosurgery</strong><br />

Active<br />

Return<br />

ESU<br />

Inhibit<br />

adapter<br />

AEM Monitor<br />

13


<strong>Electrosurgery</strong> <strong>Self</strong>-<strong>Study</strong> <strong>Guide</strong><br />

Tissue Response Technology<br />

The latest technology in electrosurgical generators uses a<br />

computer-controlled tissue feedback system that senses<br />

tissue impedance (resistance). This feedback system<br />

provides consistent clinical effect through all tissue types.<br />

The generator senses tissue resistance and automatically<br />

adjusts the current and output voltage to maintain a<br />

consistent surgical effect. This feedback system reduces<br />

the need to adjust power settings for different types of<br />

tissue. It also gives improved performance at lower power<br />

settings and voltages, which helps to reduce the risk of<br />

patient injury (Figure 24).<br />

Figure 24 – Tissue Response Technology<br />

Vessel Sealing Technology<br />

A specialized generator/instrument system has been<br />

developed that is designed to reliably seal vessels and<br />

tissue bundles for surgical ligation both in laparoscopic<br />

and open surgery applications. It applies a modified form<br />

of bipolar electrosurgery in combination with a regulated<br />

optimal pressure delivery by the instruments in order to<br />

fuse the vessel walls and create a permanent seal (Figure<br />

25).<br />

The output is feedback-controlled so that a reliable seal is<br />

achieved in minimal time independent of the type or amount<br />

of tissue in the jaws. The result is reliable seals on vessels up<br />

to 7 mm in diameter or tissue bundles with a single activation.<br />

The thermal spread is significantly reduced compared to<br />

traditional bipolar systems and is comparable to ultrasonic<br />

coagulation. The seal site is often translucent, allowing<br />

evaluation of hemostasis prior to cutting. The seal’s strengths<br />

are comparable to mechanical ligation techniques such as<br />

sutures and clips and are significantly stronger than other<br />

energy-based techniques such as standard bipolar or<br />

ultrasonic coagulation. The seals have been proven to<br />

withstand more than three times normal systolic blood<br />

pressure.<br />

14<br />

Tissue Resistance<br />

INPUT<br />

Computer Controlled<br />

OUTPUT<br />

Figure 25 – Vessel Sealing Technology<br />

Bipolar Generator<br />

• Low Voltage - 180V<br />

• High Amperage - 4A<br />

• Tissue Response<br />

Instruments<br />

• High pressure<br />

• Open (reposable)<br />

• Laparoscopic (disposable)<br />

System Operation<br />

• Applies optimal pressure to vessel/tissue bundle<br />

• Energy delivery cycle:<br />

- Measures initial resistance of tissue and<br />

chooses appropriate energy settings<br />

- Delivers pulsed energy with continuous<br />

feedback control<br />

• Pulses adapt as the cycle progresses<br />

- Senses that tissue response is complete and<br />

stops the cycle<br />

Figure 26 – Vessel Sealing System Operation<br />

Smoke<br />

Evacuation<br />

In 1994 the Association of Operating Room Nurses<br />

(AORN) first published recommended practices stating


that patients and perioperative personnel should be<br />

protected from inhaling the smoke generated during<br />

electrosurgery (AORN, 1999). Smoke evacuation should<br />

be part of room set-up whenever smoke or plume<br />

generating equipment is used. That could include<br />

electrosurgical units or lasers.<br />

Toxic fumes and carcinogens have been isolated from<br />

surgical smoke (Ulmer, 1997). Formaldehyde and<br />

benzene are but two of the substances that have been<br />

isolated from smoke. The Occupational Safety and Health<br />

Administration (OSHA), has issued a booklet with<br />

recommendations for protecting workers from the<br />

hazards of benzene (OSHA, 1987). Using protective<br />

equipment, such as a smoke evacuator, can decrease the<br />

risk associated from inhaling these substances. In<br />

September, 1996, the National Institute for Occupational<br />

Safety and Health (NIOSH) issued a hazard alert through<br />

the Centers for Disease Control’s (CDC) healthcare facility<br />

network. The alert recommended that laser and<br />

electrosurgical smoke be evacuated and filtered to protect<br />

healthcare workers (NIOSH, 1998).<br />

Patients, as well as surgical staff, are exposed to smoke<br />

during laparoscopic procedures. Researchers have<br />

determined that the byproducts contained in smoke are<br />

absorbed into the patient’s bloodstream, producing<br />

substances such as methemoglobin and<br />

carboxyhemoglobin that can pose a potential hazard to<br />

the patient (Ott, 1997).<br />

Before surgery the perioperative nurse should determine the<br />

volume of smoke that will be produced during the procedure,<br />

and select the appropriate smoke evacuation system. The<br />

vacuum source should be portable, easy to set up and use.<br />

Figure 29 – Smoke Evacuator System<br />

<strong>Electrosurgery</strong> <strong>Self</strong>-<strong>Study</strong> <strong>Guide</strong><br />

A filtration system with a triple filter offers the greatest<br />

protection. This system consists of a prefilter to filter out<br />

large particles; an Ultra Low Penetrating Air (ULPA) filter to<br />

capture microscopic particles; and a charcoal filter to adsorb,<br />

or bind to the toxic gases (Figure 27)<br />

Prefilter<br />

ULPA<br />

Charcoal<br />

Figure 27 – Triple Filter System<br />

The vacuum source should be able to pull 50 cubic feet per<br />

minute of air through the system. This ability provides the<br />

most effective evacuator, and will offer the nurse the<br />

flexibility to select the appropriate capture device to use with<br />

it. The surgical team may elect to use a carriage that mounts<br />

on the electrosurgical pencil to evacuate the smoke (Figure<br />

28).<br />

Figure 28 – Electrosurgical Pencil with Smoke Evacuation<br />

Attachment<br />

This is the most convenient method to evacuate smoke,<br />

but it may be less effective during procedures that<br />

produce a large volume of smoke. A system that gives the<br />

perioperative staff the option of selecting evacuation<br />

settings will be of use in a wide variety of surgical<br />

procedures (Figure 29).<br />

15


<strong>Electrosurgery</strong> <strong>Self</strong>-<strong>Study</strong> <strong>Guide</strong><br />

Electrosurgical<br />

Accessories<br />

Electrosurgical units are only part of the electrosurgical<br />

system. Another, integral, part is the accessories. These<br />

include active electrodes, holsters, and patient return<br />

electrodes (grounding pads).<br />

Active Electrodes<br />

Active electrodes deliver concentrated current to the<br />

target tissue. There is a wide assortment of active<br />

electrodes available for both bipolar and monopolar units.<br />

Active electrode pencils or forceps may be controlled by<br />

handswitches or foot pedals. Pencil tips are available in<br />

needles, blades, balls, and loops (Figure 30). Some active<br />

electrodes are a combined suction and coagulation<br />

instrument. As minimally invasive surgery has gained<br />

popularity, active laparoscopy electrodes have also been<br />

developed. They are available as disposable and reusable<br />

products.<br />

Figure 30 – Active Electrodes<br />

In 1991 an electrosurgical device was developed for use<br />

with the ultrasonic surgical aspirator (Figure 31). The<br />

ultrasonic surgical aspirator handpiece attaches to a<br />

command console. When in operation, the ultrasonic<br />

handpiece vibrates at a frequency of 23,000 times per<br />

second. That frequency is above the range of human<br />

hearing, thus the name ultrasonic. The device does not<br />

emit sound waves or light waves. Its vibrating tip works by<br />

contacting tissue. When it does, fragmentation occurs.<br />

16<br />

By itself, the ultrasonic handpiece provides no hemostasis.<br />

When an electrosurgical module is added to the<br />

handpiece, the surgeon is able to fragment, cut or<br />

coagulate tissue, simultaneously or independently.<br />

Figure 31 – Ultrasonic Surgical Aspirator Handpiece with<br />

Electrosurgical Module Attachment<br />

Holsters<br />

Holsters are a vital safety component of the<br />

electrosurgical system. When active electrodes are not in<br />

use, they should be placed in holsters where they will be<br />

easily accessible and visible to the surgical team. They<br />

should be of the<br />

type recommended by the manufacturer for use with<br />

electrosurgical active electrodes, and should meet<br />

standards for heat and fire resistance. Patient safety can<br />

be threatened by the use of pouches and other makeshift<br />

holsters not intended for use with electrosurgery active<br />

electrodes.<br />

Patient Return Electrodes<br />

Patient return electrodes, or grounding pads, collect the<br />

monopolar current that has entered the patient and allow<br />

it to be safely removed and returned to the generator.<br />

There are many types of patient return electrodes used,<br />

ranging from metal plates to dual section pads. Reusable<br />

metal plates are made of stainless steel and fit under the<br />

patient. With such plates, conductive gel must be used to<br />

improve the conductive plate/patient interface. The<br />

quality of contact depends on gravity and the amount of<br />

gel used. A disposable version of this plate is also used. It<br />

is made of cardboard and covered with foil. Neither type<br />

plate conforms to body contours and effectiveness may<br />

vary. Pre-gelled, disposable foam pads adapt well to body


contours and an adhesive edge helps to hold the pad on<br />

the patient. They come in many shapes and sizes. When<br />

using them, it is important to store cartons flat so that the<br />

gel does not accumulate on one side of the pad. During<br />

use the drier side of an improperly stored pad could<br />

contribute to an electrosurgical burn. Gelled pads can also<br />

dry out during long storage periods, thereby<br />

compromising their conductivity. When using gelled pads,<br />

care must be taken to rotate the stock and store the<br />

cartons properly.<br />

Conductive adhesive pads are similar to gel pads but<br />

instead of gel they use a layer of adhesive over the pad<br />

surface. The adhesive promotes conductivity and good<br />

contact with the patient’s skin. These pads may be a dry<br />

conductive adhesive or a high moisture conductive<br />

adhesive. Both conform well to body contours. A high<br />

moisture product will tend to increase patient skin<br />

conductivity during use. These types of pads are also<br />

available in the split dual section design. The split pad<br />

design incorporates an “interrogation circuit” which is part<br />

of a system to actively monitor the amount of impedance<br />

at the patient/pad interface because there is a direct<br />

relationship between this impedance and the contact area.<br />

The system is designed to deactivate the generator before<br />

an injury can occur, if it detects a dangerously high level of<br />

impedance at the patient/pad interface.<br />

It is important to place the return electrode properly on the<br />

patient. The patient return electrode should be as close as<br />

possible to the surgical site and should be positioned over a<br />

large muscle mass. Muscle conducts electrical current<br />

better than fatty tissue, scar tissue or bony prominences<br />

(Fairchild, 1997). Patient return electrodes should not be<br />

placed over metal prostheses because the scar tissue<br />

surrounding the implant increases resistance to the flow of<br />

electrical current. The pad site should be clean and dry, and<br />

free from excessive hair. The patient return electrode<br />

should not be placed where fluids are likely to pool during<br />

surgery. If the patient has a pacemaker, the patient return<br />

electrode should be placed as far away as possible so that it<br />

directs the current away from the pacemaker. The<br />

pacemaker manufacturer should be consulted to determine<br />

whether or not the pacemaker is susceptible to electrical<br />

interference. The pacemaker should be checked for proper<br />

function postoperatively.<br />

It is also important to read and follow the manufacturer’s<br />

recommendations for the patient return electrode being<br />

used. These recommendations are legal and binding<br />

<strong>Electrosurgery</strong> <strong>Self</strong>-<strong>Study</strong> <strong>Guide</strong><br />

instructions when using the product. Failure to follow<br />

recommended use could constitute negligence should an<br />

incident occur.<br />

Perioperative Care of the<br />

Patient<br />

Care of the patient during electrosurgery can be<br />

enhanced by following routine and systematic procedures.<br />

Points to include during perioperative care of the patient<br />

during electrosurgery include, but are not limited to:<br />

Preoperative<br />

• Know which Electrosurgical unit (ESU) will be used<br />

and how to use it. Consult the instruction manual for<br />

specific instructions or questions.<br />

• Have all equipment and accessories available and<br />

use only accessories designed and approved for use<br />

with the unit.<br />

• Check the operation of the alarm systems.<br />

• Avoid the use of flammable anesthetics.<br />

• Place EKG electrodes as far away from the surgery<br />

site as possible.<br />

• Do not use needle EKG monitoring electrodes, they<br />

may transmit leakage current (Atkinson, 1992).<br />

• Check the line cord and plug on the ESU. Extension<br />

cords should not be used.<br />

• Do not use any power or accessory cord that is<br />

broken, cracked, frayed or taped.<br />

• Check the biomedical sticker to insure the generator<br />

has undergone a current inspection.<br />

• Cover the foot pedal with a plastic bag.<br />

• Document the generator serial number on the<br />

perioperative record.<br />

• Record exact anatomical pad position and skin<br />

condition of the pad site.<br />

• Do not cut or alter a patient return electrode.<br />

Intraoperative<br />

• If alcohol based skin preparations are used, they<br />

should be allowed to dry prior to draping (Meeker,<br />

1991).<br />

• Use the lowest possible power settings that achieve<br />

the desired surgical effect. The need for abnormally<br />

high settings may indicate a problem within the<br />

system.<br />

17


<strong>Electrosurgery</strong> <strong>Self</strong>-<strong>Study</strong> <strong>Guide</strong><br />

18<br />

• Position cords so that people cannot trip over them.<br />

Do not roll equipment over electrical cords.<br />

• If the patient is moved or repositioned, check the<br />

patient return electrode to be sure that it is still in<br />

good contact with the patient. Patient return<br />

electrodes should not be repositioned. If the patient<br />

return electrode is removed for any reason, a new<br />

pad should be used.<br />

• When an active electrode is not in use, remove it<br />

from the surgical field and from contact with the<br />

patient. An insulated holster should always be used.<br />

• Do not coil active electrode cables, or grounding<br />

pad cables. This will increase leakage current and<br />

may present a potential danger to the patient.<br />

• If possible, avoid “buzzing” hemostats in a way that<br />

creates metal to metal arcing. If “buzzing” a hemostat<br />

is necessary, touch the hemostat with the active<br />

electrode and then activate the generator. This will<br />

help eliminate unwanted shocks to surgical team<br />

members.<br />

• Use endoscopes with insulated eye pieces.<br />

• Keep active electrodes clean. Eschar build-up will<br />

increase resistance, reduce performance, and require<br />

higher power settings.<br />

• Do not submerse active accessories in liquid.<br />

• Note the type of active electrode used on the<br />

perioperative record.<br />

• If an ESU alarm occurs, check the system to assure<br />

proper function. Document any alarm intervention.<br />

• Do not use the generator top as a storage space for<br />

fluids. Spills could cause malfunctions (Hutchisson,<br />

1998).<br />

Postoperative<br />

• Turn off the ESU.<br />

• Turn all dials to zero.<br />

• Disconnect all cords by grasping the plug, not the<br />

cord.<br />

• Inspect patient return electrode site to be sure it is<br />

clear of injury (AORN, 1999).<br />

• Inspect patient return electrode after removal. If an<br />

undetected problem has occurred, such as a burn,<br />

evidence of that burn may appear on the pad.<br />

• Discard all disposable items according to hospital<br />

policy.<br />

• Remove and discard the plastic bag covering the foot<br />

pedal.<br />

• Clean the ESU, foot pedal, and power cord.<br />

• Coil power cords for storage.<br />

• Clean all reusable accessories.<br />

Routine Care and Maintenance of<br />

ESU Equipment<br />

• Routinely replace all reusable cables and active<br />

electrodes at appropriate intervals, depending upon<br />

usage.<br />

• Have a qualified Biomedical Engineer inspect the unit<br />

at least every six months.<br />

• If an ESU is dropped, a Biomedical Engineer should<br />

inspect it before it is used again.<br />

• Replace adapters that do not provide tight<br />

connections.<br />

• Inspect “permanent” cords and cables for cracks in<br />

the insulation.<br />

Proper use and maintenance of electrosurgical equipment<br />

can prolong its life and reduce costly repairs.<br />

Summary<br />

Surgeons and perioperative nurses have the opportunity<br />

to combine their unique technical skills and knowledge<br />

with the latest technology to provide high quality patient<br />

care. Positive patient outcomes can be successfully<br />

achieved through good medical and nursing practice<br />

combined with careful documentation. The importance of<br />

skill and knowledge is especially critical during the use of<br />

electrosurgery. An educated surgeon or nurse is the<br />

patient’s best advocate.


Glossary<br />

Active Electrode<br />

An electrosurgical instrument or accessory that<br />

concentrates the electric (therapeutic) current at the<br />

surgical site.<br />

Active Electrode Monitoring<br />

A system that continuously conducts stray current from<br />

the laparoscopic electrode shaft back to the generator and<br />

away from patient tissue. It also monitors the level of stray<br />

current and interrupts the power should a dangerous level<br />

of leakage occur.<br />

Alternating Current<br />

A flow of electrons that reverses direction at regular<br />

intervals.<br />

Bipolar <strong>Electrosurgery</strong><br />

<strong>Electrosurgery</strong> where current flows between two bipolar<br />

electrodes that are positioned around tissue to create a<br />

surgical effect (usually desiccation). Current passes from<br />

one electrode, through the desired tissue, to another<br />

electrode, thus completing the circuit without entering<br />

any other part of the patient’s body.<br />

Bipolar Instrument<br />

Electrosurgical instrument or accessory that incorporates<br />

both an active and return electrode pole.<br />

Blend<br />

A waveform that combines features of the cut and coag<br />

waveforms; current that cuts with varying degrees of<br />

hemostasis.<br />

Capacitive Coupling<br />

The condition that occurs when electrical current is<br />

transferred from one conductor (the active electrode),<br />

through intact insulation, into adjacent conductive<br />

materials (tissue, trocars, etc.).<br />

Cautery<br />

The use of heat or caustic substances to destroy tissue or<br />

coagulate blood.<br />

Circuit<br />

The path along which electricity flows.<br />

Coagulation<br />

The clotting of blood or destruction of tissue with no<br />

cutting effect; electrosurgical fulguration and desiccation.<br />

Contact Quality Monitoring<br />

A system that actively monitors tissue impedance<br />

(resistance) at the interface between the patient’s body<br />

<strong>Electrosurgery</strong> <strong>Self</strong>-<strong>Study</strong> <strong>Guide</strong><br />

and the patient return electrode and interrupts the power<br />

if the contact quality and/or quantity is compromised.<br />

Current<br />

The number of electrons moving past a given point per<br />

second, measured in amperes.<br />

Current Density<br />

The amount of current flow per unit of surface area;<br />

current concentration directly proportional to the amount<br />

of heat generated.<br />

Current Division<br />

Electrical current leaving the intended electrosurgical<br />

circuit and following an alternate path of least resistance<br />

to ground; typically the cause of alternate site burns when<br />

using a grounded generator.<br />

Cut<br />

A low-voltage, continuous waveform optimized for<br />

electrosurgical cutting.<br />

Cutting<br />

Use of the cut waveform to achieve an electrosurgical<br />

effect that results from high current density in the tissue<br />

causing cellular fluid to burst into steam and disrupt the<br />

structure. Voltage is low and current flow is high.<br />

Desiccation<br />

The electrosurgical effect of tissue dehydration and<br />

protein denaturation caused by direct contact between<br />

the electrosurgical electrode and tissue. Lower current<br />

density/concentration than cutting.<br />

Diathermy<br />

The healing of body tissue generated by resistance to the<br />

flow of high-frequency electric current.<br />

Direct Coupling<br />

The condition that occurs when one electrical conductor<br />

(the active electrode) comes into direct contact with<br />

another secondary conductor (scopes, graspers). Electrical<br />

current will flow from the first conductor into the<br />

secondary one and energize it.<br />

Direct Current<br />

A flow of electrons in only one direction.<br />

<strong>Electrosurgery</strong><br />

The passage of high frequency electrical current through<br />

tissue to create a desired clinical effect.<br />

ESU<br />

ElectroSurgical Unit.<br />

19


<strong>Electrosurgery</strong> <strong>Self</strong>-<strong>Study</strong> <strong>Guide</strong><br />

Frequency<br />

The rate at which a cycle repeats itself; in electrosurgery,<br />

the number of cycles per second that current alternates.<br />

Fulguration<br />

Using electrical arcs (sparks) to coagulate tissue. The<br />

sparks jump from the electrode across an air gap to the<br />

tissue.<br />

Generator<br />

The machine that coverts low-frequency alternating<br />

current to high-frequency electrosurgical current.<br />

Ground, Earth Ground<br />

The universal conductor and common return point for<br />

electric circuits.<br />

Grounded Output<br />

The output on a electrosurgical generator referenced to<br />

ground.<br />

Hertz<br />

The unit of measurement for frequency, equal to one cycle<br />

per second.<br />

Insulation Failure<br />

The condition that occurs when the insulation barrier<br />

around an electrical conductor is breached. As a result,<br />

current will travel outside the intended circuit.<br />

Isolated Output<br />

The output of an electrosurgical generator that is not<br />

referenced to earth ground.<br />

Leakage Current<br />

Current that flows along an undesired path, usually to<br />

ground; in isolated electrosurgery, RF current that regains<br />

its ground reference.<br />

Monopolar <strong>Electrosurgery</strong><br />

A surgical procedure in which only the active electrode is<br />

in the surgical wound; electrosurgery that directs current<br />

through the patient’s body and requires the use of a<br />

patient return electrode.<br />

Monopolar Output<br />

A grounded or isolated output on an electrosurgical<br />

generator that directs current through the patient to a<br />

patient return electrode.<br />

Ohm<br />

The unit of measurement of electrical resistance.<br />

Pad<br />

A patient return electrode.<br />

20<br />

Patient Return Electrode<br />

A conductive plate or pad (dispersive electrode) that<br />

recovers the therapeutic current from the patient during<br />

electrosurgery, disperses it over a wide surface area, and<br />

returns it to the electrosurgical generator.<br />

Power<br />

The amount of heat energy produced per second,<br />

measured in watts.<br />

Radio Frequency<br />

Frequencies above 100 kHz that transmit radio signals;<br />

the high-frequency current used in electrosurgery.<br />

Resistance<br />

The lack of conductivity or the opposition to the flow of<br />

electric current, measured in ohms.<br />

RF<br />

Radio frequency.<br />

Tissue Response Technology<br />

An electrosurgical generator technology that continuously<br />

measures the impedance/resistance of the tissue in<br />

contact with the electrode and automatically adjusts the<br />

output accordingly to achieve a consistent tissue effect.<br />

Vessel Sealing Technology<br />

An electrosurgical technology that combines a modified<br />

form of electrosurgery with a regulated optimal pressure<br />

delivery by instruments to fuse vessel walls and create a<br />

permanent seal.<br />

Volt<br />

The unit of measurement for voltage.<br />

Voltage<br />

The force that pushes electric current through resistance;<br />

electromotive force or potential difference expressed in<br />

volts.<br />

Watt<br />

The unit of measurement for power.<br />

Waveform<br />

A graphic depiction of electrical activity that can show<br />

how voltage varies over time as current alternates.


References<br />

AORN Standards and Recommended Practices for<br />

Perioperative Nursing (1999). Denver: Association of<br />

Operating Room Nurses.<br />

Atkinson, L. J. Fortunato, N.M. (1996). Berry & Kohn’s<br />

Operating Room Technique. (8th Ed.). St. Louis: Mosby.<br />

Chernow, B.A., & Vallasi, G.A. (1993). The Columbia<br />

Encyclopedia (5th Ed). New York: Columbia University<br />

Press<br />

ECRI (1995). Are Bovie CSV and other spark-gap<br />

electrosurgical units safe to use? Health Devices 24(7). 293-<br />

294.<br />

ECRI (1999). <strong>Electrosurgery</strong>. Operating Room Risk<br />

Management (Jan, 1999). 1-15.<br />

Fairchild, S.S. (1997). Perioperative nursing: principles and<br />

practice (2nd Ed.). Boston: Little, Brown. 341-345.<br />

Grundemann, B. J., & Fernsebner, B. (Eds.). (1995).<br />

Comprehensive Perioperative Nursing (Vol.1). Boston:<br />

Jones and Bartlett.<br />

Harrell, G.J., & Kopps, D.R. (1998). Minimizing patient risk<br />

during laparoscopic electrosurgery. AORN Journal, 67(6).<br />

1194-1205.<br />

Harris, F.W. (1978). A primer on basic electricity for a<br />

better understanding of electrosurgery. Boulder: Valleylab.<br />

Henderson, M. (1999). A matter of choice: the insulscan<br />

insulation tester. Surgical Services Management, 5(8). 8-<br />

10.<br />

Hutchisson, B.; Baird, M.G.; & Wagner, S. (1998).<br />

<strong>Electrosurgery</strong> safety. AORN Journal, 68(5). 830-837.<br />

Kirshenbaum, G. & Temple, D.R. (1996). Active electrode<br />

monitoring in laparoscopy: the surgeon’s perspective.<br />

Surgical Services Management, 2(2). 46-49.<br />

Lister, E. C.(1984). Electric circuits & machines (6th Ed.).<br />

New York: McGraw-Hill.<br />

Medical Data International (MDI). US Surgical Procedure<br />

Volumes (1996) Exhibits 6-1 & 6-2.<br />

<strong>Electrosurgery</strong> <strong>Self</strong>-<strong>Study</strong> <strong>Guide</strong><br />

Meeker, J. J. , & Rothrock, J. C. (1999). Alexander’s Care<br />

of the Patient in Surgery (11th Ed.). St. Louis: Mosby.<br />

Mitchell, et al. (1978). A handbook of surgical diathermy.<br />

Bristol: John Wright & Sons.<br />

National Institute for Occupational Safety and Health<br />

(NIOSH) (Mar.,1998). Control of smoke from laser/electric<br />

surgical procedures. Cincinnati: NIOSH Department of<br />

Health and Human Services publication no. 96-128.<br />

Occupational Safety and Health Administration (1987).<br />

Hazards of Benzene (OSHA 3099). Washington, DC: US<br />

Government Printing Office.<br />

Ott, D.E. (1997). Smoke and Particulate Hazards During<br />

Laparoscopic Procedures. Surgical Services Management<br />

3(3). 11-12.<br />

Pearce J.A. (1986) <strong>Electrosurgery</strong>. New York: John Wiley<br />

& Sons.<br />

Rothrock, J.C. (1999) The RN First Assistant (3rd Ed.).<br />

Philadelphia: Lippincott. 327-333.<br />

Tucker, R.D. (1998). Understanding electrosurgery better.<br />

Contemporary Urology (October, 1998). 68-83.<br />

Ulmer, B.C. (1997). Air quality in the OR. Surgical Services<br />

Management, 3(3). 18-21.<br />

21


<strong>Electrosurgery</strong> <strong>Self</strong>-<strong>Study</strong> <strong>Guide</strong><br />

<strong>Self</strong>-<strong>Study</strong> <strong>Guide</strong> Test Questions<br />

1.) Electricity always seeks<br />

a.) the path of most resistance to return to earth ground.<br />

b.) the path of most resistance to return to its source.<br />

c.) the path of least resistance to return to earth ground.<br />

d.) the path of least resistance to return to its source.<br />

2.) The properties of electricity include<br />

a.) current, circuit, resistance and voltage.<br />

b.) current, ground, current and voltage.<br />

c.) current, resistance, hertz and voltage.<br />

d.) current, circuit, ground and amperage.<br />

3.) Neuromuscular stimulation from the flow of alternating<br />

electric current ceases at frequencies above<br />

a.) 50,000 cycles per second.<br />

b.) 100,000 cycles per second.<br />

c.) 200,000 cycles per second.<br />

d.) 350,000 cycles per second.<br />

4.) When current concentration/density is high<br />

a.) the resistance is reduced.<br />

b.) the resistance is unaffected.<br />

c.) heat is produced.<br />

d.) heat is dissipated.<br />

5.) A patient return electrode is not required when using<br />

bipolar electrosurgery because<br />

a.) the voltage is too low to cause an injury.<br />

b.) the voltage is confined to the target tissue.<br />

c.) the current is confined between the two poles of<br />

the instrument.<br />

d) the current disperses in the tissue at the tip of the<br />

instrument.<br />

6.) As the current concentration is increased<br />

a.) the power setting requirement is decreased.<br />

b.) the power setting requirement is increased.<br />

c.) the heat produced in the tissue remains the same.<br />

d.) the heat produced in the tissue is decreased.<br />

7.) The cutting waveform can be modified to provide<br />

simultaneous hemostasis (blended waveform) by<br />

a.) decreasing the voltage and increasing the duty<br />

(on/off) cycle.<br />

b.) increasing the voltage and decreasing the duty cycle.<br />

c.) decreasing the voltage and decreasing the duty cycle.<br />

d.) increasing the voltage and increasing the duty cycle.<br />

8.) Contact quality monitoring is a system that<br />

a.) constantly monitors the quality of the pad/patient<br />

interface.<br />

b.) constantly monitors the quality of the generator/pad<br />

22<br />

interface.<br />

c.) combines isolated and interrogation circuitry to<br />

monitor output.<br />

d.) combines isolated and interrogation circuitry to<br />

monitor resistance.<br />

9.) The hazards associated with endoscopic<br />

electrosurgery use include all of the following except<br />

a.) direct coupling.<br />

b.) current division.<br />

c.) insulation failure.<br />

d.) capacitive coupling.<br />

10.) Tissue response technology incorporates a<br />

computer-controlled tissue feedback system that<br />

a.) automatically changes the power settings.<br />

b.) automatically reduces the amount of power required.<br />

c.) senses the conductivity of the target tissue.<br />

d.) senses the impedance/resistance of the target<br />

tissue.<br />

11.) The smoke produced from the electrosurgical<br />

device is<br />

a.) not as harmful as laser plume and need not be<br />

evacuated.<br />

b.) not as harmful as laser plume, but should be<br />

evacuated.<br />

c.) potentially as harmful as laser plume and<br />

evacuation is recommended.<br />

d.) potentially as harmful as laser plume and<br />

evacuation is optional.<br />

12.) The site selected for the patient return electrode<br />

should be all of the following except<br />

a.) over a large muscle mass.<br />

b.) as close to the surgical site as possible.<br />

c.) protected from fluid invasion.<br />

d.) close to a pacemaker to divert the current.<br />

13.) Vessel sealing technology is incorporated into a<br />

specialized electrosurgical generator that combines<br />

a.) modified monopolar electrosurgery with<br />

regulated pressure delivery.<br />

b.) modified bipolar electrosurgery with regulated<br />

pressure delivery.<br />

c.) increased voltage electrosurgery with decreased<br />

pressure delivery.<br />

d.) decreased voltage electrosurgery with decreased<br />

pressure delivery.<br />

Test Key<br />

13.) b<br />

9.) b<br />

10.) d<br />

11.) c<br />

12.) d<br />

5.) c<br />

6.) a<br />

7.) b<br />

8.) a<br />

1.) c<br />

2.) a<br />

3.) b<br />

4.) c


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<strong>Electrosurgery</strong> <strong>Self</strong>-<strong>Study</strong> <strong>Guide</strong><br />

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<strong>Electrosurgery</strong> <strong>Self</strong>-<strong>Study</strong> <strong>Guide</strong><br />

24


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